Hypervelocity projectile

ABSTRACT

1. A spherical hypervelocity projectile which comprises a solid spherical central core of high strength metal, a fiberglass filament winding wound about said central core, and a plastic, high-sound-speed material secured about said filament winding.

Atkins et a1.

[ 1 HYPERVELOCITY PROJECTILE [76] Inventors: Walter W. Atkins, 7417Yellowstone Dr., Alexandria, Va. 22312; Mario A. Persechino, 5700Roberts Dr., Brinkley Manor. Temple Hills, Md. 20031 {22] Filed: Mar.21, 1962 [21] Appl. No.: 181,491

[52] US. Cl l02/92.3; 102/52 [51] Int. Cl. F42B 11/26 [58] Field ofSearch 102/52, 56, 66, 67, 68, 102/69, 92, 92.5, 92.5 G, 70, 64, 92.1,92.2, 92.3, 92.4

[56] References Cited UNITED STATES PATENTS 1,202,162 10/1916 Clay102/52 2,343,344 3/1944 Thompson 102/52 2,401,380 6/1946 Teitscheid102/52 2,766,692 10/1956 Mynes 102/67 2,937,597 5/1960 Winn et al.102/105 Aug. 5, 1975 FOREIGN PATENTS OR APPLICATIONS 1,237,195 6/1960France 102/67 OTHER PUBLICATIONS Primary ExaminerStephen C. BentleyAssistant Examinerlordan C, T.

Attorney, Agent, or Firm-R. S. Sciascia; Arthur Branning; M. L. CraneEXEMPLARY CLAIM l. A spherical hypervelocity projectile which comprisesa solid spherical central core of high strength metal, a fiberglassfilament winding wound about said central core, and a plastic,high-sound-speed material secured about said filament winding.

2 Claims, 3 Drawing Figures I-IYPERVELOCITY PROJECTILE The inventiondescribed herein may be manufactured and used by or for the Governmentof the United States of America for governmental purposes without thepayment of any royalties thereon or therefor.

The present invention is directed to projectiles and more particularlyto projectiles capable of making deep penetrations when impacted againstobjects traveling at hypervelocities.

Heretofore, objects used for penetrating the surface of airships, etc.,included solid materials such as rods, shaped explosive charges,spheres, fragments, bullets such as armor piercing projectiles, etc.These objects have their drawbacks. Armor piercing projectiles aredirectional and must strike the surface at a specific angle. Objectssuch as fragments, spheres, cubes, etc., break up into tiny particles asa result of hypervelocity impact. For purposes of this invention,hypervelocity is defined as the velocity at which a projectile shattersupon impact with the target surface. Such impacts produce hemisphericalcraters on the surface of the impact object with a depth to diameterratio for impacts under these conditions of about one-half whichrepresents wide shallow craters on the surface. Armor piercingprojectiles, shaped charges, rods, etc., require orienta tion ordirection in order to be effective upon impact. Under certaincircumstances there is a requirement wherein orientation or direction isnot possible, which decreases the effectiveness of the last mentionedtype.

The present invention is directed to a high strength, compositehypervelocity projectile which is effective as a kill mechanism againstobjects traveling at a hypervelocity, such as ICBM, IRBM, satellites,space ships, etc.

It is therefore an object of the present invention to provide aprojectile capable of deep penetrations when impacted against objectstraveling at hypervelocities.

Another object is to provide a projectile effective against objectstraveling at hypervelocities without a requirement of orientation ordirection of the projectile.

While another object is to provide a projectile which is easy tofabricate to any desired size.

Still another object is to provide a projectile suitable forhypervelocity kills without the projectile breaking into many tinyparticles upon impact.

Yet another object is to provide a projectile which will have maximumpenetration upon impact with a body traveling at a hypervelocity.

Other and more specific objects of the invention will become apparentupon a careful consideration of the following detailed description whentaken together with the accompanying drawing in which:

FIG. 1 illustrates a cross-sectional view of a composite type projectileof this invention; and

FIGS. 2 and 3 are modifications of FIG. 1.

Referring now to the drawing there is illustrated, by example, in FIG.I, a cross-sectional view of a projectile made according to the presentinvention. The projectile, as shown, comprises a central core 11 of highstrength and high density material coated with a low acousticalimpedance material 12, such as a filamentwound impregnated phenolicfiberglass cord and with an outside shell 13 of high impedance and highmodulus of elasticity material such as an outer shell of copper ortungsten carbide, however, the outer shell may be made of othermaterials, such as plastic.

FIG. 2 illustrates a modification of FIG. I which illustrates aprojectile which has a core surrounded by a coating 14 of plastic withfiberglass mixed in the plastic. This forms a composite coating on thecore.

FIG. 3 illustrates a modification of FIG. I in which the core is made ofan explosive mixture 15 which will explode under favorable conditionsafter impact and with the same low acoustical impedance material 12about the core and with a plastic coating as the outer shell.

In operational use, the projectiles may be fired in the path of anobject or distributed in a large pattern in the path of enemy spaceships or other type objects without any specific orientation of theprojectile. Since the projectiles are spherical it does not matter fromwhich direction the projectile strikes the object. When dealing withvery high velocity objects, the effect on the object will be the samewhether the object runs into the projectile or whether the projectilehas a direct hit on the object.

When a projectile strikes an object or an object has an impact with theprojectile, there occurs an elastic or diaphragmatic dishing of thesurface of the object, which distributes the resistance over aconsiderable area and causes the stress of impact to react upon theprojectile which tends to stop the projectile in a very short distance.Usually when projectiles of the prior art type strike an objecttraveling at a high velocity, the impact breaks the projectile into manyparticles such that the degree of penetration into the object isconsiderably reduced. It is well known that standard armorpiercingprojectiles will withstand shocks of impact, however, these projectilesare directional and require a specific orientation with respect to theobject.

The projectiles of the present invention do not require a specialorientation and yet are capable of penetrating surfaces of high velocityobjects. When the projectile of the present invention has an impact witha high velocity object, the energy of the impact is transmitted to thecenter sphere through the outer shell and the low acoustical impedancematerial about the core. The covering absorbs, reflects, and dissipatesa substantial portion of the shocks that are generated upon impact andproduces an elastic or diaphragmatic dish ing of the surface of theobject. The high strength wrapping of fiberglass cord or other materialssurrounding the center core is resistant to both the effects of theshock and break-up while the plastic covering causes dishing of thesurface. The energy on impact required for the elastic dishing isconcentrated at the point of impact and therefore partially absorbed bythe plastic covering. After impact, the metal core or sphere is sloweddown because of energy dissipation and achieves a slower velocity, whichshould permit the projectile to penetrate the surface of the objectwithout breaking up into small particles.

The modification illustrated by FIG. 2 combines the fiberglass with theplastic to provide a single covering. In this modification the coveringwould require greater energy to break up on impact and will have aslightly different effect on the velocity of the sphere as it continuesto make an impact with the surface of the object struck.

The modification as illustrated by FIG. 3 makes use of an explosivematerial as the center or core which may be capable of reflecting anddissipating the shock energy during impact. The shock energy duringimpact being absorbed by the plastic covering and the fiberglass cordwhich surrounds the explosive core. Such a structure permits theexplosive charge to penetrate the surface hit sufficiently to producethe greatest damage upon exploding.

The projectiles of the present invention have the advantages of havingno limit in size of fabrication; do not require special orientation uponimpact, therefore the ratio of projectile weight to total warhead weightis larger than warheads which require projectile orientation;projectiles are easily fabricated and produce deep penetration of anobject when hit by the projectile or when the projectile is hit byobjects traveling at hypervelocities.

Obviously many modifications and variations of the present invention arepossible in the light of the above secured about said filament winding.

* l I I

1. A spherical hypervelocity projectile which comprises a solidspherical central core of high strength metal, a fiberglass filamentwinding wound about said central core, and a plastic, high-sound-speedmaterial secured about said filament winding.
 2. A sphericalhypervelocity projectile which comprises a solid spherical central coreof high strength metal, a fiberglass filament winding wound about saidcentral core, and a metal, high-sound-speed material secured about saidfilament winding.